7[degrees]C, beginning in March in South Louisiana, it is estimated to take at least 9-12 wk for March hatchlings to grow large enough to appear in the daily harvest--not enough time for February or later burrowing
females based on the results of this study and the DD estimates of McClain (in press).
However, if the number of entrances is used as an index of beaver burrowing
activity and density it can be a reliable indicator.
trials were conducted using a ten gallon tank filled with about 10 cm of substrate (washed sand).
owl is one of our charismatic birds, it's a symbol of the wide open spaces we once had in Southern California," said Daniel Cooper, a conservation biologist, who owns Pasadena-based Cooper Ecological Monitoring Inc.
choice of sites and burrow fidelity are critical parameters to evaluate, as they determine the energetic costs of burrowing
to an animal during its lifetime.
We document two nesting attempts of a female Burrowing
Owl within the same breeding season in widely separated locations (Arizona and Saskatchewan) that required crossing the Rocky Mountains in between the two previously known migration routes.
Large burrows observed in photographs were created by the deep burrowing
Fifteen Western Burrowing
Owls (Athene cunicularia hypugaea) were captured over two winters (2001-2003) in southern Texas and examined for ectoparasites.
owls' habit of bringing mammal dung to their burrows is an example of tool use, researchers say.
Few native species are as widely distributed and appear as adaptable to environmental change as Burrowing
Owls (Athene cunicularia).
Only 31 species have been documented to use burrows of desert tortoises, including two birds, the common poorwill (Phalaenoptilus nuttallii) and burrowing
owl (Athene cunicularia; Luckenback, 1982).
Aller, a marine geochemist at the State University of New York at Stony Brook, said he was struck by Ziebis' innovative use of an acrylic-walled observation room sunk deep into the sediment (lower photo), enabling divers for the first time to directly measure the activities of animals burrowing
beneath the sea.
Early observations of Florida Burrowing
Owls (Athene cunicularia floridana) describe their propensity to excavate burrows in short grass habitat (Hoxie 1889, Rhoads 1892, Scott 1892, Palmer 1896).
Distribution of Burrowing
Owls on public and private lands in Colorado.
owls use the gopher tortoise's burrows to shelter their fledgling owlets.